26 January 2024

Genes and social class

It has been estimated that the proportion of a person’s intelligence which is inherited from his or her parents is upward of 50 percent.

However, there is great resistance to the idea of heritable intelligence.

A theory popular with some academics is that Victorian and Edwardian middle-class intellectuals believed in heritability because it fitted with the view that the class structure of society was fine as it was. Francis Galton, author of the 1869 book Hereditary Genius, is among those accused of defending this view. Galton was the first to study twins to determine the relative contributions of ‘nature versus nurture’, a phrase he coined. In a 2001 paper on Galton,* David Burbridge quotes history professor Simon Szreter who claims that:
‘Galton provided an important new intellectual leadership for the view that factors of heredity, and not environment, were the source of all observable class and race differences. ... Galton himself was almost exclusively interested in social class differentials in British society. [He was] one of the principal ideologues and champions of a professional meritocracy as providing the constitutional ideal for British society ... his hereditarian, professional model was the paradigm English meritocratic representation of social structure.’
Using the pejorative term ‘ideologue’, Professor Szreter makes Galton sound like an apologist for the class structure of Victorian Britain.

However, David Burbridge points out that whatever Galton’s private views on this issue were, in his public writings he was wary of making assertions of the kind that Professor Szreter attributes to him.
... nowhere does Galton put any weight on his study of twins to support a claim for a hereditary basis of the differences between social classes. But what in fact were Galton's views on heredity and social class? It is surprisingly difficult to answer this question. Galton’s published comments on social class are few and scattered. Nor, at least until very late in his career, do his private notes and correspondence show much interest in the structure of British society.
Academics hostile to the idea of heritability may find it useful to paint a picture of their opponents as dogmatic, and biased by personal interests. At least in Galton’s case, this picture, David Burbridge argues, is wrong.
[Galton’s] apparent reluctance to engage in any explicit and extended discussion of social class and social mobility may have stemmed from an awareness that quantitative data were lacking. On at least two occasions he called for investigations in this area. At some point Galton himself appears to have planned an enquiry into social mobility.

* David Burbridge, ‘Francis Galton on Twins, Heredity and Social Class’, British Journal for the History of Science, 34, pp.323-340. The quotation by Simon Szreter is taken from his book Fertility, Class and Gender in Britain 1860-1940, Cambridge University Press, 1996.